Change count+malloc to realloc in parse_gasses

Instead of counting the amount of ',' delimiters in the gasses string
and then using malloc, realloc on every now token. This prevents a bug
when there are consecutive ',' delimiters (in which case nof_gasses and
the amount of tokens returned by strtok do not match).

1 files changed, 19 insertions, 24 deletions

diff --git a/src/opendeco.c b/src/opendeco.c
index 6c2be17..926ff50 100644
--- a/src/opendeco.c
+++ b/src/opendeco.c
@@ -103,43 +103,38 @@ void print_segment_callback_fn(const decostate_t *ds, segtype_t type, void *arg)
 
 int parse_gasses(gas_t **gasses, char *str)
 {
-    if (!str) {
-        *gasses = NULL;
-        return 0;
-    }
-
-    /* count number of gasses in string */
-    int nof_gasses = 1;
+    int nof_gasses = 0;
+    *gasses = NULL;
 
-    for (int c = 0; str[c]; c++)
-        if (str[c] == ',')
-            nof_gasses++;
+    if (!str)
+        return nof_gasses;
 
-    /* allocate gas array */
-    gas_t *deco_gasses = malloc(nof_gasses * sizeof(gas_t));
-
-    /* fill gas array */
-    char *gas_str = NULL;
-    int gas_idx = 0;
+    char *token = NULL;
 
     for (;;) {
-        if (!gas_str)
-            gas_str = strtok(str, ",");
+        if (!token)
+            token = strtok(str, ",");
         else
-            gas_str = strtok(NULL, ",");
+            token = strtok(NULL, ",");
 
-        if (!gas_str)
+        if (!token)
             break;
+        else
+            nof_gasses += 1;
 
-        if (scan_gas(&deco_gasses[gas_idx], gas_str)) {
-            wprintf(L"Invalid gas (%s). Aborting!\n", gas_str);
+        *gasses = realloc(*gasses, nof_gasses * sizeof(gas_t));
+
+        if (*gasses == NULL) {
+            wprintf(L"Cannot reserve space. Aborting!\n");
             exit(EXIT_FAILURE);
         }
 
-        gas_idx++;
+        if (scan_gas(&(*gasses)[nof_gasses - 1], token)) {
+            wprintf(L"Invalid gas (%s). Aborting!\n", token);
+            exit(EXIT_FAILURE);
+        }
     }
 
-    *gasses = deco_gasses;
     return nof_gasses;
 }